Patent GB-189910306-A (GB)
Title: Improvements in the Construction of Type-writing Machines.
Inventor: JENSEN PETER
Filed: 1899-05-16
Granted: 1900-04-28
Abstract: 10,306. Jeasen, P., [Hanson, A., and Lee, O. H.]. May 16. Type-writers. -Relates to a type-writer having a vertical platen which in the process of writing a page is always turned in the same direction, a margin key being provided which, when depressed on the completion of a line, causes the platen to move forward sufficiently to bring the predetermined marginal line again to the impression point, and at the same time lifts the platen to enable a new line to be commenced. The platen J is mounted on a base piece Y formed with a vertical central tube Y' extending through the platen. The tube Y<1> is of square section internally, so as to be free to slide vertically, but without rotation, on the square shaft P<3>, which extends upwards from the escapement-wheel O<3>. Annular plates C<2>, Z' on the platen are connected by a rod c<2> on which slide a pair of annular paper clamps D<2>, consisting of flat metallic spring bands open at one point for the introduction and removal of the paper and carrying a number of small rollers which hold the paper in firm contact with the platen. A vertical feed-rol'er is also journalled in the plates C<2>, Z', the clamps D' being curved outwardly for its reception close to their openings. The paper is introduced by turning the platen in contact with the feed-roller, the plates C<2>, Z' being at that time prevented from rotation, which their frictional mounting on the platen ensures when the type-writer is in operation. The platen is free to turn within a frame consisting of uppar and lower cross-bars K', J<1> and vertical side bars of T-section adapted to slide in grooved standards H forming part of the machine frame. The platen is constantly urged upwards by the tension of a cord I<4>, which is secured to the lower cross-bar J<1> and passes upwards over a pulley mounted at the top of one of the standards H and thence downwards to the guide-pulley J<4> and spring drum G<4>. An escapement controlled by the line-spacing key acts in conjunction with a rack on one of the side-bars of the platen frame, and is shown detached in Fig. 7. A lever N<2> is pivoted to one of the standards at u<2>, and is under control of a spring which normally maintains the lug w<2> against an adjustable stop beneath it. A finger S' projecting from the lever N<2> forms the pivot for a plate R<2> bearing a fixed dog i<3> and a vertically-sliding dog j<3>. By depressing the finger S<2>, both dogs can be moved away from the rack on the platen frame so as to completely release the latter, or by the depresion of the rod T<2>, which is connected with the line-spacing key lever, the dog i<3> can be disengaged from the rack and the dog j<3> swung into its place. The rack in that case rises through one or two teeth according to the position of the cam U<2> which limits the downward movement of the dog j<3>. When the line-spacing key is released, the dog i<3> returns into engagement with the rack. The standards are connected by a curved cross-piece K having rearwardly-extending arms L. The inking-rihbon L' passes through a guide M' carried by a bell-crank lever e controlled by a spring k. The ribbon is wound on spools N' mounted on vertical shafts N, either of which can be driven by bevel gearing from a horizontal shaft K<2>. The shaft K<2> is driven by reversible bevel gearing from the shaft B<4>, on which is mounted a spring drum S<3>. The depression of the platen in commencing a new page turns the drum G<4>, which is connected with the shaft B' by a pawl P' and ratchet-wheel O<4>, the spring Q<4> being thus intermittently wound up, and the inking-ribbon at the same time advanced. A ratchet-wheel D' with an anchor-escapement or detent prevents reverse rotation of the shaft B'. The drum S<3> is connected by a cord R<3> with a small pulley Q<3> on the shaft P<3>, the rotation of which is controlled by the letter-spacing escapement-wheel O<3>. The typebars U, u are pivoted upon an arc-shaped bar P carried by the shift-levers Q. Each type-bar bears two characters U', the faces of which slant in opposite directions. The key levers T, pivoted on a rod G', are linked to the type-bars by rods T', and are controlled by springs V<1>. The shift-levers Q are linked by a rod R to the shift key. lever S<1>, by the depression of which the shift-levers can be thrown into the position indicated in dotted lines for printing upper-case characters. A locking- cam W enables the shift-levers to be permanently fixed in the rearward position for printing wholly in capitals &c. Letter-spacing is effected in the following manner :-A universal bar b<1>, carried by a pair of levers C' rigidly secured to a shaft B', lies beneath the key levers T, and can also be depressed by means of the wrist-bar D and lever E'. To the shaft B' is also secured a lever W<3> shown in section in Fig. 9. The forward end of the lever W<3> is attached to a link H<3> formed with a loop d<4> and secured above to an escapement dog k<4>, Fig. 10, pivoted at j<4>. This dog is normally in engagement with the escapement-wheel O<3>, but the spring-controlled sliding dog p<4> takes its place when the lever W<3> is depressed, and permits the escapement-wheel to advance one tooth. By pushing in the rod A<3> both dogs can be withdrawn from the escapement-wheel, the platen being then free to turn for inserting a sheet of paper &c. When a line is nearly completed, the bell S', Fig. 1, is caused to sound by the action of a pin projecting from a wheel T<3>. On the completion of the line the operator depresses the " margin-key," which causes the depression of the lever V<3>, Fig. 9, and also of the line-spacing key lever. The link P causes the segment F<3> to turn, throwing the plate B<3> into the path of a stop U<3> on the wheel T<3>, and at the same time retracting the sliding plate E<3>, Fig. 10, so as to withdraw both dogs from the escapement-wheel. The platen now turns until the marginal line determined by the position of the stop U<3> is reached, and at the same time it rises in consequence of the depression of the line-spacing key lever. The next depression of one of the key levers will, as before described, depress the lever W<3>, throwing the segment F<3> back to the position show in Fig. 9, releasing the stop U<3> for a further advance of the platen, and at the same time bringing the escapement dogs once more into engagement with the wheel O<3>.